From c0daf721ea840a6fd39baf92a32f56e6fb993712 Mon Sep 17 00:00:00 2001
From: p_caiwfeng <p_caiwfeng@tencent.com>
Date: Mon, 6 Dec 2021 14:44:40 +0800
Subject: [PATCH] fix too many open files bug

---
 core/tcpserver.go  | 21 +++++++++++++++++++--
 core/tunhandler.go | 10 +++++++++-
 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/core/tcpserver.go b/core/tcpserver.go
index 738d6810..be03a64a 100644
--- a/core/tcpserver.go
+++ b/core/tcpserver.go
@@ -4,11 +4,10 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	log "github.com/sirupsen/logrus"
 	"github.com/wencaiwulue/kubevpn/util"
 	"net"
 	"time"
-
-	log "github.com/sirupsen/logrus"
 )
 
 type fakeUDPTunConnector struct {
@@ -236,3 +235,21 @@ func (c *fakeUDPTunnelConn) WriteTo(b []byte, addr net.Addr) (n int, err error)
 	}
 	return len(b), nil
 }
+
+func (c *fakeUDPTunnelConn) Close() error {
+	return c.Conn.Close()
+}
+
+func (c *fakeUDPTunnelConn) CloseWrite() error {
+	if cc, ok := c.Conn.(interface{ CloseWrite() error }); ok {
+		return cc.CloseWrite()
+	}
+	return nil
+}
+
+func (c *fakeUDPTunnelConn) CloseRead() error {
+	if cc, ok := c.Conn.(interface{ CloseRead() error }); ok {
+		return cc.CloseRead()
+	}
+	return nil
+}
diff --git a/core/tunhandler.go b/core/tunhandler.go
index 41b404f7..729ba3c8 100644
--- a/core/tunhandler.go
+++ b/core/tunhandler.go
@@ -135,7 +135,15 @@ func (h *tunHandler) findRouteFor(dst net.IP) net.Addr {
 
 func (h *tunHandler) transportTun(tun net.Conn, conn net.PacketConn, raddr net.Addr) error {
 	errChan := make(chan error, 2)
-	defer conn.Close()
+	defer func() {
+		if c, ok := conn.(interface{ CloseRead() error }); ok {
+			_ = c.CloseRead()
+		}
+		if c, ok := conn.(interface{ CloseWrite() error }); ok {
+			_ = c.CloseWrite()
+		}
+		_ = conn.Close()
+	}()
 	ctx, cancelFunc := context.WithCancel(context.Background())
 	remote.CancelFunctions = append(remote.CancelFunctions, cancelFunc)
 	go func() {